Multi-boson production including vector-boson scattering and photon-photon fusion at ATLAS

Measurements of multiple electroweak bosons production and vector boson scattering, as well as photon-photon fusion at the LHC are stringent tests of the electroweak sector and provide a model-independent means to search for new physics at the TeV scale. In this talk, we present recent results from the ATLAS experiment for multi-boson production in proton-proton collisions at √s=13 TeV. Differential cross sections of inclusive diboson final states and diboson final states in association with jets are measured and the data are compared to theoretical predictions at NLO (and NNLO) in perturbative QCD. We also present results on ZZ and Zgamma production via vector-boson scattering. For some of the measurements reinterpretation in terms of an effective field theory to constrain new physics beyond the Standard Model are also presented. Finally, we will also present results of the observation of photon-induced WW production and photon-induced di-lepton production. If available, we will also present new results on multiboson production.